Considering the large number of magnetic stirring hot plates that are damaged or unused in chemical laboratories, this Technology Report presents guidelines for students to be able to diagnose problems, and repair and maintain magnetic stirring hot plates using common and low-cost parts, or even repurposed materials. In addition, this paper presents a control board for stirring or heating with a circuit that uses the triode for alternating current BTA08, as well as various suggestions for refurbishing, maintaining, and replacing parts. Guidelines are provided for diagnosing equipment and conducting a cost analysis to determine the economic viability of proposed maintenance and repair approaches.